def implement_security_policy(model, policy):
    """
    实施安全策略
    :param model: 模型
    :param policy: 安全策略
    :return: 实施完成的模型
    """
    for key, value in policy.items():
        if key == "encryption" and value:
            model.enable_encryption()
        elif key == "access_control" and value:
            model.enable_access_control()
        elif key == "backup" and value:
            model.enable_backup()
        elif key == "monitoring" and value:
            model.enable_monitoring()
    return model

# 示例
model = "YourModel"
policy = define_security_policy()
implemented_model = implement_security_policy(model, policy)
print(f"Implemented model: {implemented_model}")